Alert archive / New Jersey / Special Marine Warnings in 2021

Special Marine Warning 4, NWS Philadelphia/Mount Holly

February 22, 2021

NWS Philadelphia/Mount Holly issued this special marine warning at Feb 22, 2021, 2:32 PM EST. It was in force for 118 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Feb 22, 2021, 2:32 PM EST (19:32 UTC)
Expired
Feb 22, 2021, 4:30 PM EST
In force
118 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.0 in
Wind
34.0 mph

The radar

The Dover AFB radar (KDOX), 67 km from the middle of the area, began a volume at 19:35 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 12:00Z, 7.5 hours before the alert went out and 84 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Wallops Is Stn, VA at 12:00Z on 2021-02-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 2021-02-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 362 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1225 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
362 m²/s²
0-3 km storm-relative helicity
398 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

570 
WHUS51 KPHI 221932
SMWPHI
ANZ431-454-455-475-222130-
/O.NEW.KPHI.MA.W.0004.210222T1932Z-210222T2130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service Mount Holly NJ
232 PM EST Mon Feb 22 2021

The National Weather Service in Mount Holly NJ has issued a

* Special Marine Warning for...
  Lower Delaware Bay...
  Coastal waters from Cape May NJ to Fenwick Island DE out 20 nm...
  Outer waters from Cape May NJ to Fenwick Island DE out 20 to 40
  nm...

* Until 430 PM EST.

* At 232 PM EST, showers were located along a line extending from
  near Overfalls Shoal to 8 nm north of Chincoteague Bay, moving east
  at 30 knots.

  HAZARD...Wind gusts 34 knots or greater.

  SOURCE...Radar.

  IMPACT...Small craft could be damaged in briefly higher winds and 
           suddenly higher waves.

* Locations impacted include...
  Overfalls Shoal, Five Fathoms Buoy, Fenwick Island, Cape Henlopen,
  Rehoboth Beach, Bethany Beach, Delaware Lightship Buoy 44009, Buoy
  2ms and Indian River Inlet Bridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Seek safe shelter immediately. Mariners can expect gusty winds and 
increasing waves.

&&

LAT...LON 3845 7503 3845 7510 3851 7511 3853 7514
      3850 7522 3853 7528 3893 7514 3867 7416
      3861 7417 3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 1932Z 265DEG 31KT 3887 7505 3814 7535 

HAIL...0.00IN
WIND...>34KTS

$$

CMS
4 follow-up statements
685 
FZUS71 KPHI 222013
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
313 PM EST Mon Feb 22 2021

ANZ431-454-455-475-222130-
/O.CON.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
313 PM EST Mon Feb 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 430 PM EST...

For the following areas...
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm...
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm...
Delaware Bay waters south of East Point NJ to Slaughter Beach DE...
Waters from Cape May NJ to Fenwick Island DE out 20 to 40 nm...

At 312 PM EST, showers were located along a line extending from near 
Buoy 4fb to African Queen Wreck, moving east at 40 knots. Strong 
wind gusts will occur for up to an hour behind the line of showers.

HAZARD...Wind gusts to 40 knots.

SOURCE...Radar indicated.

IMPACT...Small craft could be damaged in briefly higher winds and 
         suddenly higher waves.

Locations impacted include...
Overfalls Shoal, Five Fathoms Buoy, Fenwick Island, Cape Henlopen,
Rehoboth Beach, Bethany Beach, Delaware Lightship Buoy 44009, Buoy
2ms and Indian River Inlet Bridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are 
expected.

&&

LAT...LON 3845 7503 3845 7510 3851 7511 3853 7514
      3850 7522 3853 7528 3893 7514 3867 7416
      3861 7417 3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2012Z 270DEG 38KT 3886 7449 3817 7491 

HAIL...0.00IN
WIND...40KTS

$$

CMS
048 
FZUS71 KPHI 222032
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
332 PM EST Mon Feb 22 2021

ANZ431-222042-
/O.CAN.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
332 PM EST Mon Feb 22 2021

...THE SPECIAL MARINE WARNING IS CANCELLED...

The affected areas were...
Lower Delaware Bay...

The showers have moved out of the warned area and no longer pose a 
significant threat to boaters.

LAT...LON 3843 7495 3883 7477 3867 7416 3861 7417
      3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2032Z 265DEG 31KT 3887 7429 3818 7471 

$$

ANZ454-455-475-222130-
/O.CON.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
332 PM EST Mon Feb 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 430 PM EST...

For the following areas...
Coastal waters from Cape Henlopen to Fenwick Island DE out 20 nm...
Coastal waters from Cape May NJ to Cape Henlopen DE out 20 nm...
Waters from Cape May NJ to Fenwick Island DE out 20 to 40 nm...

At 332 PM EST, showers were located along a line extending from 7 nm
southwest of Deepwater Reef to 6 nm north of Jackspot Reef, moving 
east at 30 knots. Strong winds will occur well behind the band of 
showers.

HAZARD...Wind gusts to 40 knots.

SOURCE...Radar indicated.

IMPACT...Small craft could be damaged in briefly higher winds and 
         suddenly higher waves.

Locations impacted include...
Five Fathoms Buoy and Delaware Lightship Buoy 44009. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are 
expected.

&&

LAT...LON 3843 7495 3883 7477 3867 7416 3861 7417
      3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2032Z 265DEG 31KT 3887 7429 3818 7471 

HAIL...0.00IN
WIND...40KTS

$$

CMS
577 
FZUS71 KPHI 222058
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
358 PM EST Mon Feb 22 2021

ANZ454-455-222108-
/O.CAN.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
358 PM EST Mon Feb 22 2021

...THE SPECIAL MARINE WARNING IS CANCELLED...

The affected areas were...

Coastal waters from Cape May NJ to Fenwick Island DE out 20 nm...

The showers have moved out of the warned area and no longer pose a 
significant threat to boaters.

LAT...LON 3835 7471 3876 7449 3867 7416 3861 7417
      3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2058Z 265DEG 31KT 3889 7401 3820 7443 

$$

ANZ475-222130-
/O.CON.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
358 PM EST Mon Feb 22 2021

...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 430 PM EST...

For the following areas...
Waters from Cape May NJ to Fenwick Island DE out 20 to 40 nm...

At 358 PM EST, showers were located along a line extending from 10 nm
southeast of Deepwater Reef to near Chicken Bone, moving east at 30
knots. Strong winds will occur well behind the main band of showers.

HAZARD...Wind gusts to 40 knots.

SOURCE...Radar indicated.

IMPACT...Small craft could be damaged in briefly higher winds and 
         suddenly higher waves.

The showers will remain over mainly open waters.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Move to safe harbor immediately as gusty winds and high waves are 
expected.

&&

LAT...LON 3835 7471 3876 7449 3867 7416 3861 7417
      3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2058Z 265DEG 31KT 3889 7401 3820 7443 

HAIL...0.00IN
WIND...40KTS

$$

CMS
955 
FZUS71 KPHI 222127
MWSPHI

Marine Weather Statement
National Weather Service Mount Holly NJ
427 PM EST Mon Feb 22 2021

ANZ475-222137-
/O.EXP.KPHI.MA.W.0004.000000T0000Z-210222T2130Z/
427 PM EST Mon Feb 22 2021

...THE SPECIAL MARINE WARNING WILL EXPIRE AT 430 PM EST...

The affected areas were... 

Outer waters from Cape May NJ to Fenwick Island DE out 20 to 40 nm...

The showers have moved out of the area and no longer pose a
significant threat to boaters.

LAT...LON 3835 7471 3876 7449 3867 7416 3861 7417
      3851 7426 3831 7427 3822 7431
TIME...MOT...LOC 2127Z 265DEG 31KT 3891 7372 3822 7414 

$$

CMS

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Feb 22, 2:22 PM ESTSpecial Marine WarningPHI113 min

Nearby

Special Marine Warnings in New Jersey, 2021Every special marine warning in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.